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Designing studies to investigate client-treatment matching.

The process of designing studies of client-treatment matching involves a number of methodological complexities. Besides the large number of potential client characteristics and a range of possible outcome variables, a variety of treatment attributes can be matched including modality, intensity, duration, format, setting, therapist and goal. Hindsight matching designs (which can include hypothesis testing) examine interactions between client characteristics and treatments to which they were not intentionally matched. Foresight matching designs involve a prospective experimental test of a matching hypothesis, comparing the outcomes of cases matched by specific decision rules with other cases not so matched. Under certain conditions, these hindsight and foresight matching designs are logically equivalent. Mathematical modeling of clinical judgment offers yet another promising avenue for future studies of matching schemas. Glaser's core-shell strategy provides a practical model for implementing clinical systems and research on matching within ongoing services.

Alcoholism↗

Patterns of dietary intake and serum lipids interact with proteinuria as risk factors for progression of chronic renal failure.

UNLABELLED: This prospective study assessed the interactions between patterns of nutrient intake and serum lipids with other risk factors for progression of chronic renal failure. The study cohort consisted of 52 individuals with documented chronic renal failure, 18 women and 34 men, with a mean age of 65 +/- 11 years at the time of recruitment. The dependent variable was the rate of progression of chronic renal failure, which was determined by the slope of the curve generated from five or more values of the reciprocal of serum creatinine (SCr-1) and divided by time (in months of follow-up) for each patient, and recorded in dung/month. The independent variables included dietary factors (phosphorus, protein); serum lipids (total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides); proteinuria; serum phosphorus; serum albumin; serum glucose; and blood pressure. Serum creatinine was drawn in a fasting state and determined using the picric acid technique on five or more occasions for each patient. The mean monthly rate of decline in dL/mg/month was calculated for each patient. The cohort was followed for 1.5 years. Descriptive statistics were determined for all variables. Analysis of principal components was used to generate variables representing patterns of nutrient intake and serum lipids. The outcome variable was modeled using stepwise linear regression which included principal components representing dietary and serum lipid patterns. The Student's t test and the F test were used for hypothesis testing. All tests were significant at p < 0.05. RESULTS AND CONCLUSIONS: Multicolinearity prevented the inclusion of more than one individual dietary or serum lipid variable into the multiple linear regression model of rate of decline in kidney function. Principal components representing patterns of dietary intake and serum lipids, contributed to the prediction of rate of decline in renal function together with proteinuria.

Adolescent↗

[Testing linkage hypothesis in hybrid analysis of alternatively distributed behavioral traits with incomplete penetrance].

The use of polymorphic microsatellite markers for mapping alternatively distributed behavioral traits with incomplete penetrance was studied with special reference to inheritance of predisposition to catalepsy in mice. Using only backcrosses as a segregating population, the major gene for catalepsy was with high likelihood mapped to region 30-75 cM of murine chromosome 13. It was also established that this gene determines 20% of the trait penetrance whereas the remaining 31% of the observed penetrance are accounted for by numerous polygenes.

Animals↗

Consistency in performance evaluation reports and medical records.

BACKGROUND: In the health care market managed care has become the latest innovation for the delivery of services. For efficient implementation, the managed care organization relies on accurate information. So clinicians are often asked to report on patients before referrals are approved, treatments authorized, or insurance claims processed. What are clinicians responses to solicitation for information by managed care organizations? The existing health literature has already pointed out the importance of provider gaming, sincere reporting, nudging, and dodging the rules. AIMS OF THE STUDY: We assess the consistency of clinicians reports on clients across administrative data and clinical records. METHODS: For about 1,000 alcohol abuse treatment episodes, we compare clinicians reports across two data sets. The first one, the Maine Addiction Treatment System (MATS), was an administrative data set; the state government used it for program performance monitoring and evaluation. The second was a set of medical record abstracts, taken directly from the clinical records of treatment episodes. A clinician s reporting practice exhibits an inconsistency if the information reported in MATS differs from the information reported in the medical record in a statistically significant way. We look for evidence of inconsistencies in five categories: admission alcohol use frequency, discharge alcohol use frequency, termination status, admission employment status, and discharge employment status. Chi-square tests, Kappa statistics, and sensitivity and specificity tests are used for hypothesis testing. Multiple imputation methods are employed to address the problem of missing values in the record abstract data set. RESULTS: For admission and discharge alcohol use frequency measures, we find, respectively, strong and supporting evidence for inconsistencies. We find equally strong evidence for consistency in reports of admission and discharge employment status, and mixed evidence on report consistency on termination status. Patterns of inconsistency may be due to both altruistic and self-interest motives. DISCUSSION AND LIMITATIONS: Payment contracts based on performance may be subject to provider mis-reporting, which could seriously undermine its purpose. However, further analysis is needed to determine how much of the inconsistencies observed are results of clinician gaming in reporting. IMPLICATIONS FOR HEALTH POLICY: Increasing system accountability is becoming more and more important for health care policy makers. Results of this study will lead to a better understanding of physician reporting behavior. IMPLICATIONS FOR FUTURE RESEARCH: Our work in this paper on the data sets confirms the statistical significance of strategic reporting in alcohol addiction treatment. It will be of interest to confirm our finding in other data sets. Our on-going research will model the motives behind strategic reporting. We will hypothesize that both altruistic and financial incentives are present. Our empirical identification strategy will use Maine s Performance-Based Contracting system and client insurance sources to test how these incentives affect the direction of clinician s strategic reporting.

Adult↗

Patterns of comprehension performance in agrammatic Broca's aphasia: a test of the Trace Deletion Hypothesis.

We tested the core prediction of the Trace Deletion Hypothesis (TDH) of agrammatic Broca's aphasia, which contends that such patients' comprehension performance is normal for active reversible sentences but at chance level for passive reversible sentences. We analyzed the comprehension performance of 38 Italian Broca's aphasics with verified damage to Broca's area, who completed sentence-to-picture matching tasks using active and passive reversible sentences as stimuli. The results failed to confirm the predictions made by TDH: only a small minority (15%) performed at chance on passive sentences and better than chance on active sentences. Furthermore, the distribution of the 38 subjects' performance on passive sentences differed from that predicted by the TDH since many more subjects performed at better-than-chance levels than expected. We discuss the implication of these results for claims about the distribution of language processing mechanisms in the brain.

Adult↗